This invention relates to a cap seal for drums.
When a drum or drum can is filled with contents and a plug is thereafter screwed into the mouthpiece on the cylindrical mouth of the can, a cap seal is fitted over the pluged mouth for sealing. For this purpose cap seals made of metal are known which comprise a circular top wall and a peripheral wall and has an inverted U-shaped vertical section. Such cap seal is fitted over the cylindrical mouth of drum using a sealing tool. The cap seal is placed over the cylindrical mouth by the hand, and the peripheral lower end portion of the seal is pressed inward by the sealing tool to deform the peripheral end portion along the outwardly projecting upper edge of the mouthpiece. Thus the sealing procedure with the use of cap seal is very troublesome and inefficient, requires skill and the tool, and is therefore costly.